obliged to say to an unprepared class: "I did not realize how hard
that lesson was, or I would not have assigned so much"; or, "That
lesson was longer than I intended." All of which is a confession that
the teacher was unprepared to make the assignment properly. It is
true that the teacher is very busy and has many lessons to prepare;
but, on the other hand, the teacher who keeps a day ahead of the class
in his preparation will find that it abundantly pays in the greater
mastery of his subject and the time saved in reviewing it preparatory
to the recitation. This is not time lost, it is time saved.

The young teacher's lack of knowledge of the principles underlying the
art of study is a more serious matter, and a difficulty harder to
overcome. Every teacher should make a special study of the psychology
of attention and interest. He should also come to know how the mind
naturally approaches any new subject, first securing a _synthetic_ or
bird's-eye view of it as a whole; how next it _analyzes_ it into its
elements; and how finally it thinks them together, or _synthesizes_
them, into a new and better-understood whole.

4. _How to assign a lesson_

There may, of course, be some lessons that can properly be assigned in
a moment by telling the class how much to take in advance. This is
true of lessons that are only a continuation of matter with which the
class are already somewhat familiar, which they know how to study, and
which contains no special difficulties. For example, spelling lessons
presenting no new difficulties or especially hard words; arithmetic
lessons containing practice problems intended for drill, but no new
topics for study; grammar lessons consisting of applications of
principles or rules already mastered. But all lessons that are built
upon a logical outline, or contain new or difficult principles, or
involve especial difficulties of any kind should be assigned carefully
and with sufficient detail to make sure that the class know how to go
to work in preparing the lesson without loss of time and interest.

It is necessary, however, to observe a caution in this connection.
There is some danger of assigning lessons in such a way as to render
too much help, and thus relieve the pupil of the necessity of
mastering it for himself. It is difficult to say whether the mistake
of helping too much in the assignment, or not helping enough is the
more serious. The teacher must know his class and his textbook,